Spinoff of bug 1309130 comment #10
One of the things that will help move clients from Firefox 47.0.2 is a partial mar since 47.0.2 is a watershed and we've seen how watersheds tend to cause a significant rise in clients on older versions. It would be best to wait until 50.0.1 is released.

We can include 47.0.2 in the list of partials for 50.0.1 as a part of ship-it submission, so we generate them as a part of release automation. ATM we can't generate more than 3 partials there (some TC limitations), so we may need to repeat the steps we've done for 43.0.1.

Looks like it worked better this time and the update verify tests are passing 47.0.2 (still in progress). I think we are good to go. The update will be available in sync with other partials generated by release automation, except that these ones are win32/win64 only.

This worked fine in Firefox 51.0b4.
Next step will be separating integrity verification and balrog verification logic into 2 separate tests. In this case we could test MAR file even before we upload them to the candidates directory.

With 50.0.2 release there is no longer a partial mar file to update from 47.0.2.
Looks like 50.0 to 50.0.2 is also a complete mar file.
Rail, shall I file a new bug or would you prefer that I reopen this one.

Hmm, I'm not sure this is going to scale if we start back filling partials manually. Currently we are limited to 3 partials in release automation and use the top 3 used versions. I'd like to tackle this issue (partials on demand) next year.
In any case, if you feel that we need to generate partials from 50.0, please file a separate bug, we'll handle it.

(In reply to Robert Strong [:rstrong] (use needinfo to contact me) from comment #13)
> What about from 47.0.2 to latest?
I can help investigate and actioning this. will discuss more offline as to the 'how to'

didn't use mozreview bc there is already a tools repo patch attached to this bug.
* this was largely created via running commands like: https://bugzilla.mozilla.org/show_bug.cgi?id=1319905#c3 but with s/50.0.1/50.1.0 and s/1/2 for any build-num places.
* the diff is created against current FIREFOX_50_1_0_RELEASE_RUNTIME tag
* I didn't add "47.0.2 build information" or "past-update" info for 47.0.2 as I don't think we have to since we did for 47.0.2->50.0.1 tools patch so they are there already